A video posted on YouTube shows a driver constantly honking their horn behind two cyclists.

KMGH

Images from a YouTube video of an encounter between two cyclists and a driver near Longmont.

dfriel1/YouTube

BOULDER COUNTY, Colo. -
An investigation into a viral video has led to a traffic citation. The YouTube video shows a driver in an SUV slowly following two cyclists and honking repeatedly in Boulder County.

Wednesday, Colorado State Patrol identified the driver as James Ernst, 75.

Ernst was issued a citation by the Colorado State Patrol for harassment, impeding the flow of traffic and improper use of a horn or warning device.

The cyclists involved told 7NEWS that what began as a quiet Sunday morning ride east of Longmont turned into a frightening ordeal.

Dirk Friel said he and his friend did nothing to provoke Ernst's tirade, but tried to keep it from escalating.

"I was just, like, this is insane. I'm not sure if this is going to get ugly." said Friel. "He was definitely the one who could do more damage to us than us to him."

The two-lane road has no shoulder and the cyclists are riding on the far right line.

Friel said the older man behind the wheel kept following them, honking his horn for more than five minutes.

"This is getting old," you can hear one of the cyclists say on the video.

"What's even worse is we saw him approaching from behind and to be polite, we ride [sic] single file to give him as much road as possible, as we did with every other car we encountered on this road," the cyclist wrote on YouTube. "This guy was so intent of bugging us that he backed up traffic behind him and cars had to pass him on a double yellow line."

The cyclists said they eventually slowed down to force the driver to pass them.

After Friel posted the video, another cyclist commented online that he had had a similar incident with the same man a few weeks ago.

7NEWS reporter Jaclyn Allen tracked the license plate number to a home in Erie, but the Ernst's son, David Ernst, said his father was not home.

"I don’t know what happened," said the son, David Ernst, who's seen the video. "Maybe there was something that precipitated it. I don’t know, because he’s a gentle old man."

A 2009 State law allows drivers to cross a yellow line to pass cyclists if it is clear.

"Under Colorado law, bicycles are vehicles just like a car or truck or motorcycle," Dan Grunig of Bicycle Colorado told 7NEWS. "So we have the same rights and the same rules to follow" as other vehicles.

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